Abstract

Background

Although body mass index (BMI) is the most widely accepted parameter for defining
obesity, recent studies have indicated a unique set of patients who exhibit normal
BMI and excess body fat (BF), which is termed as normal weight obesity (NWO). Increased
BF is an established risk factor for atherosclerosis. However, it is unclear whether
NWO subjects already have a higher degree of vascular inflammation compared to normal
weight lean (NWL) subjects; moreover, the association of BF with vascular inflammation
in normal weight subjects is largely unknown.

Methods

NWO and NWL subjects (n = 82 in each group) without any history of significant vascular
disease were identified from a 3-year database of consecutively recruited patients
undergoing 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG-PET/CT) at a self-referred Healthcare Promotion Program. The degree of subclinical
vascular inflammation was evaluated using the mean and maximum target-to-background
ratios (TBRmean and TBRmax) of the carotid artery, which were measured by 18 F-FDG-PET/CT (a noninvasive tool for assessing vascular inflammation).

Conclusions

NWO is associated with a higher degree of subclinical vascular inflammation, of which
BF is a major contributing factor. These results warrant investigations for subclinical
atherosclerosis in NWO patients.